Olefinic and acetylenic azasilacyclopentanes

ABSTRACT

Azasilacyclopentanes of the general formula ##STR1## are prepared by reacting a dialkoxyalkyl(3-chloro-2-alkylpropyl)silane with a Grignard reagent of the formula R 1  MgBr in the presence of an ether, to make an alkoxyalkylalkenyl(3-chloro-2-alkylpropyl)silane which is reacted with acetyl chloride and a Lewis acid to make chloroalkylalkenyl(3-chloro-2-alkylpropyl)silane which is then reacted with an amine of the formula R 3  NH 2  to make the azasilacyclopentanes.

This is a divisional of copending application(s) Ser. No. 07/656,540filed Feb. 15, 1991.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to azasilacyclopentanes and a method of preparingit. This invention also relates to specific intermediate compounds,methoxymethylvinyl(3-chloro-2-methylpropyl)silane andchloromelthylvinyl(3-chloro-2-methylpropyl)silane.

2. Background Information

A search for new crosslinkers for use in the preparation of roomtemperature vulcanizing silicones (RTV's) lead to the discovery of theazasilacyclopentanes of the present invention. Speier in U.S. Pat. No.3,146,250, issued Aug. 25, 1964, disclosed nitrogen-containing cyclicsilanes and their preparation, which is hereby incorporated by referenceto show the preparation of the nitrogen-containing cyclic silanes.Speier teaches nitrogen-containing cyclic silanes of the general formula##STR2## wherein R is a hydrogen atom, a monovalent hydrocarbon radical,a monovalent hydrocarbon radical containing divalent oxygen in the formof an ether linkage, an aminoalkyl radical, an aminophenyl radical, ahalogenphenyl radicals, and an organosilyl radical of the generalformula (XR)Y₂ Si- in which Y is a monovalent hydrocarbon radical and Xis chlorine, bromine or iodine, R' is a divalent hydrocarbon radicalwith 3 to 6 carbon atoms between the bonds with the nitrogen atom andthe silicon atom, R" is a monovalent hydrocarbon radical, a monovalenthydrocarbon radical with divalent oxygen as an ether linkage, an alkoxyradical, an alkoxy radical containing divalent oxygen as an etherlinkage, and a phenoxy radical. Speier teaches preparing these compoundsby reacting a halogeno-alkylhalogenosilane of the formula ##STR3## withan amino compound of the formula RNH₂. Speier also discloses makingsiloxanes having the unit formula ##STR4## by hydrolyzing and condensinga compound of the formula ##STR5## where Z is an alkyl radical, a phenylradical, or an alkyl radical containing divalent oxygen in the form ofether linkages, and a is 0 to 2. Speier also teaches making endblockeddiorganosiloxanes by effecting a reaction between

    HO(R'".sub.2 SiO).sub.a H

and ##STR6## to produce a siloxane of the formula ##STR7##

THE INVENTION

This invention relates to an azasilacyclopentane of the general formula##STR8## in which each of R¹, R², R³, and R⁴ is independently selectedfrom the group consisting of a hydrogen atom and a monovalenthydrocarbon radical, where one of R¹, R², and R³ is a monovalenthydrocarbon radical with olefinic unsaturation or acetylenicunsaturation. The monovalent hydrocarbon radicals include methyl, ethyl,propyl, butyl, phenyl, vinyl, allyl, hexenyl, cyclohexyl, tolyl, andisopropyl. Preferably, R¹, R², or R³, when an olefinically oracetylenically unsaturated monovalent hydrocarbon radical, is olefinicand either vinyl or allyl.

The azasilacyclopentanes of the present invention can be prepared froman dialkoxy(chloroalkyl)silane of the general formula ##STR9## where R⁵is an alkyl radical of from 1 to 5 carbon atoms per molecule, includingmethyl, ethyl, propyl, isopropyl, butyl, isobutyl, and pentyl, by firstmaking a monoalkoxyalkylalkenyl-(3-chloro-2-alkylpropyl)silane of thegeneral formula ##STR10## by reacting silane (I) with a Grignard reagentof the general formula R¹ MgBr in the presence of a solvent such asdiether ether, tetrahydrofuran, or a mixture thereof. One preferredmonoalkoxyalkylalkenyl(3-chloro-2-alkylpropyl)silane ismethoxymethylvinyl(3-chloro-2-methylpropyl)silane. After the silane (II)is obtained, it can be reacted with acetyl chloride in the presence of aLewis acid, preferably ferric chloride to make achloroalkylalkenyl(3-chloro-2-alkylpropyl)silane of the general formula##STR11## One preferred chloroalkylalkenyl(3-chloro-2-alkylpropyl)silaneis chloromethylvinyl(3-chloro-2-methylpropyl)silane.

The azasilacyclopentanes of the present invention can be made by aprocess described by Speier where a halogenoalkylhalogenosilane of theformula ##STR12## is reacted with an amino compound of the formula RNH₂.The present invention relates to making azacyclopentanes from specificchloroalkylalkenyl(3-chloro-2-alkylpropyl)silanes (formula III) whichare new compounds. Speier is hereby incorporated by reference to showthe known general reaction of chlorosilanes with an amino compound tomake certain nitrogen-containing compounds as described herein.

These azasilacyclopentanes are useful for making polyorganosiloxaneswhich have reactive endgroups in the presence of moisture and do notproduce leaving groups upon reaction.

The following examples are presented for illustrative purposes andshould not be construed as limiting the present invention which isproperly delineated in the claims. In the following examples, Me=methyland Vi=vinyl.

EXAMPLE 1

1,2,4-Trimethyl-1-vinyl-2-aza-silacyclopentane was prepared. To asolution of 50.0 g (254 mmol) ofdimethyoxymethyl(3-chloro-2-methylpropyl)silane in 250 ml of diethylether in a three-necked, 1 L (liter) round-bottom flask fitted with amechanical stirrer, nitrogen inlet, and addition funnel was added over aone hour period, a solution of 290 ml (290 mmol) of 1M (molar) vinylmagnesium bromide in tetrahydrofuran (THF). The reaction was allowed tostir overnight under a nitrogen atmosphere at room temperature and theslightly yellowish liquid was decanted from the solids. The solventswere removed at 40° C. and 9 mmHg to yield 68.09 g of a yellow liquidwith considerable amounts of solids. To this was added 50 ml of benzeneand the salts were removed by filtration through a course glass fritfunnel. The collected solids were washed with two 30 ml portions ofbenzene. The combined organic fractions were stripped at 50° C. and 9 mmHg to yield 40.19 g of liquid with a small amount of salts. The resultsof gas chromatography-mass spectroscopy (GC-MS) showed the followingcomposition of the liquid: ##STR13##

3.1 wt % of 9 unidentified impurities at an order of magnitude lowerlevel.

The mass spectra was used to identify these compounds and the resultswere:

For B compound: 192, not observed, M⁺ ; 165(10) M-Vi; 137 (10),NA;121(210), (MeO)ViClSi⁺ ; 109(230), (MeO)MeClSi⁺ ; 101(780), (MeO)MeViSi⁺; 56(1000), C₄ H₈ ⁺, where data are presented as charge(m/e), (relativeintensity).

For C compound: 188, not observed, M⁺ ; 161(8) M-Vi; 117 (280), Vi₂ClSi⁺ ; 105(284), MeViSi⁺ ; 97(489), Vi₂ MeSi⁺ ; 56(1000), C₄ H₈ ⁺.

For D compound: 204, not observed, M⁺ ; 177(10), M-Vi; 121 (290),(MeO)ViClSi⁺ ; 113(620), (MeO)Vi₂ Si⁺ ; 56(1000), C₄ H₈ ⁺.

The ²⁹ Si nuclear magetic resonance(NMR) had one major peak at 6.63 ppmrelative to tetramethylsilane. The crude product was purified by shortpath distillation. The fraction boiling at 75° C. at 6 mm Hg weighed28.22 g (58% yield) and was compound B,methoxymethylvinyl(3-chloro-2-methylpropyl)silane.

Chloromethylvinyl(3-chloro-2-methylpropyl)silane was prepared. A mixtureof 28.00 g (143.3 mmol) of compound B in 15.5 ml (17.10 g, 217.9 mmol,1.5 eq) of acetyl chloride was allowed to sit at ambient temperature for12 hours. A slight exotherm was noted. The low boiling material wasremoved by distillation and the product distilled at 88° C. to 90.5° C.and 30 mm Hg to give 25.2 g of material (88% yield). The product waschloromethylvinyl(3-chloro-2-methylpropyl)silane as was identified by ¹³C NMR: 134.79 and 134.73 and 134.68 (1:2:1, 1.67), SiVi; 52.93 (1.00),CH₂ Cl; 31.51 and 31.48 (0.83, CH; 22.88 and 22.84 (0.97), CHMe; 20.13and 20.10 (1.01), SiCH₂ ; 0.59 and 0.54 (0.68), SiMe and by ²⁹ Si NMR:17.81 and 17.78 (1:1), where data are presented as ppm, (relativeintensity).

1,2,4-Trimethyl-1-vinyl-2-aza-silacyclopentane was prepared. Methylaminewas condensed into a 1 L round-bottom flask and distilled from sodium.To 490 ml (340 g, 11 mol) of methylamine was slowly added 309.8 g (1.57mol) of chloromethylvinyl(3-chloro-2-methylpropyl)silane, which resultedin two phases. The two phase system was transferred to a Parr reactorand heated at 110° C. and 230 psig for 10 hours. The reaction mixturewas cooled to -10° C., transferred to a 2 L round-bottom flask and 400ml of cold pentane was added. The layers were separated, and the upperorganic phase concentrated. After concentration, some ammonium salts hadprecipitated. These salts were removed by filtration and the productpurified by distillation at reduced pressure to yield about 160 g (60%yield) of cyclic silazane with a small amount of ammonium salts. Thedistilled product was 97% pure1,2,4-Trimethyl-1-vinyl-2-aza-silacyclopentane with two major higherboiling impurities (about 1 wt % each) and numerous minor higher boilingimpurities. The GC-MS data was:1,2,4-Trimethyl-1-vinyl-2-aza-silacyclopentane, Retention Time 2.00 min;155 (365), M⁺ ; 154 (243), M⁺ -H; 140(97), M⁺ -Me; 126 (113), M⁺ -Vi;113 (962), M⁺ -C₃ H₇ ; 112 (1000), M⁺ -C₃ H₇ ; 89 (396), MeViSiN═CH₂ ⁺ ;71 (465) MeViSiH⁺. The ¹³ C NMR spectra (ppm) was: 138.23 and 137.98,terminal vinyl; 132.86 and 137.98, internal vinyl; 62.19 and 61.92,N--CH₂ ; 33.93 and 33.80, methine; 32.09 and 32.06, NMe; 21.48 and21.54, CHMe; 21.23 and 20.95 Si--CH₂ ; -3.43 and -4.29, SiMe. The ²⁹ SiNMR had peaks at 6.229 and 6.039 relative to tetramethylsilane.

EXAMPLE 2

1,1,4-Trimethyl-2-allyl-2-aza-silacyclopentane was prepared.Chlorodimethyl(3-chloro-2-methylpropyl)silane (100 g, 0.54 mol) wasslowly added to 211.73 g (3.71 mol, 6.87 eq) of undistilled allyl amineresulting in an exothermic reaction. This reaction mixture was stirredat room temperature for 15 hours, heated to reflux at atmosphericpressure for 72 hours, and heated to 120° C. under about 50 psigpressure for 16 hours. The following GC-MS ratios shown in Table Iexemplified the reactions progression and the spectra observed were asshown.

                                      TABLE I                                     __________________________________________________________________________    RETENTION                                                                             15 HOURS                                                                            24 HOURS                                                                            72 HOURS                                                                            16 HOURS                                            TIME, MIN                                                                             20° C.                                                                       REFLUX                                                                              REFLUX                                                                              120° C.                                                                      COMPOUND                                      __________________________________________________________________________    2.70    0.0   3.9   21.3  71.9  E                                             2.82    0.0   1.0    1.1  0.9   F                                             3.20    50.4  11.0   4.1  0.0   G                                             5.19    29.5  63.0  40.2  0.0   H                                             8.46    20.0  8.8    8.1  2.4   I                                             9.58    0.0   9.3   10.1  6.1   J                                             10.58   0.0   3.1   15.1  18.7  K                                             __________________________________________________________________________

Compound E was 1,1,4-trimethyl-2-allyl-2-aza-silacyclopentane and thespectra was 169 (819), M⁺ ; 154 (1326), M⁺ -CH₃ ; 142 (1074), M⁺ -Vi;127 (375), M⁺ -C₃ H₆ ; 126 (354), M⁺ -C₃ H₇ ; 100 (784), M-69; 86(8734), Me₂ SiN═CH₂ ⁺ ; 59 (10000), Me₂ SiH⁺. Compound F not determined.

Compound G was chlorodimethyl(3-chloro-2-methylpropyl)silane and thespectra was 184 (0), M⁺ ; 169 (233), M⁺ -Me; 137 (292), M⁺ -47; 113 and115 (2459 and 1991), Cl₂ MeSi⁺ ; 93 (9786), ClMe₂ Si⁺ ; 56 (10000), C₄H₈.

Compound H was allylaminodimethyl(3-chloro-2-methylpropyl)silane and thespectra was 205 (10), M⁺ ; 190 (79), M⁺ -Me; 170 (153), M⁺ -Cl; 149(618), M⁺ -C₄ H₈ ; 134 and 136 (1263 and 508), M⁺ -CH₃ --C₄ H₈ ; 120 and122 (1250 and 625), unassigned; 114 (10000), CH₂ ═CHCH₂ NHSiMe₂ ⁺ ; 98(4709), unassigned; 93 and 95 (4999 and 1948), ClMe₂ Si⁺.

Compound I was1,1,3,3-tetramethyl-1,3-bis(3-chloro-2-methylpropyl)disiloxane and thespectra was 314 (0), M⁺ ; 187 and 189 (2045 and 1291), ClMe₂ SiOSiMeCl⁺; 167 and 169 (10000 and 3897), ClMe₂ SiOSiMe₂ ⁺.

Compound J was1,1,3,3-tetramethyl-1-(3-chloro-2-methylpropyl)-1-(3-allylamino-2-methylpropyl)disiloxaneand the spectra was 335 (0), M⁺ ; 320 (52), M⁺ -Me; 167 and 169 (1216and 463), ClMe₂ SiOSiMe₂ ⁺ ; 70 (10000), CH₂ ═CHCH₂ NH═CH₂ ⁺.

Compound K was1,1,3,3-tetramethyl-1,3-bis(3-allylamino-2-methylpropyl)disiloxane andthe spectra was 356 (0), M⁺ ; 170 (1017), CH₂ ═CHCH₂ NHCH₂ CH(CH₃)CH₂SiMe₂ ⁺ ; 169 (1177), peak 170-H; 70 (10000), CH₂ ═CHCH₂ NH═CH₂ ⁺.

Upon cooling the product of the reaction, a two phase system resulted.The upper phase weighed 111.85 g and contained most of the product1,1,4-trimethyl-2-allyl-2-aza-silacyclopentane. The lower phase weighed177.12 g and was an amber viscous liquid. This lower phase wasconcentrated at atmospheric pressure with a pot temperature of 120° C.to 122 g. Another 4.0 g of the upper phase was separated upon cooling.The combined product phases were distilled under vacuum. After a slowevolution of allylamine, the product codistilled with an ammonium saltat 78° C. and 30 mmHg. Filtration gave 51.63 g (56% yield) ofessentially pure 1,1,4-trimethyl-2-allyl-2-aza-silacyclopentane. The ¹³C NMR was: 138.13, vinyl; 114.39, vinyl; 58.98, allyl CH₂ ; 50.31, ringCH₂ N; 31.88, CH; 21.94 and 21.50, SiCH₂ and C--Me; 0.22 and -0.76,SiMe. The ²⁹ Si NMR spectra had one peak at 15.56 ppm relative totetramethylsilane.

That which is claimed is:
 1. Analkoxyalkylalkenyl(3-chloro-2-alkylpropyl)silane.
 2. Thealkoxyalkylalkenyl(3-chloro-2-alkylpropyl)silane in accordance withclaim 1 which is methoxymethylvinyl(3-chloro-2-methylpropyl)silane.
 3. Achloroalkylalkenyl(3-chloro-2-alkylpropyl)silane.
 4. Thechloroalkylalkenyl(3-chloro-2-alkylpropyl)silane according to claim 3which is chloromethylvinyl(3-chloro-2-methylpropyl)silane.